We all have learned this 9 nifty tricks in class, and they still help us every day

We learn a lot of things in school, and although we don’t use a lot of them on a daily basis, there are a few tricks that are still 100% relevant to our daily lives.

Here are a few of our favorites:

How to calculate how much time before sunset

This one is super easy. With your fingers touching, simply place your left hand up to the sky with the palm facing you; place it so that the bottom of the sun touches the top of your index finger. Now, count the number of fingers it takes to touch the horizon. Each finger represents 15 minutes; therefore, four fingers between the sun and the horizon mean there are 60 minutes left before the sun sets, three fingers mean 45 minutes are left, and so on and so on.

How to tell the number of days in a month

Make fists using both your hands and start counting the months using your knuckles and the spaces in between them. If the month lands on a knuckle, it has 31 days. If it lands in the space between, it has 30 (or less, in the case of February).

How to tell if the moon is waxing or waning

To tell if the moon is waxing or waning, you just need to remember these three letters: O, D and C. If the moon looks like an O, it is full. If it looks like a C it is waning, and if it looks like a D, it is waxing.

How to remember Roman numerals

To remember Roman numerals, keep the following phrase in mind: My Dear Cat Loves Xtra Vitamins Intensely. In this sentence, the first letter of each word represents the Roman numerals going in descending order. Therefore, M is 1,000, D is 500, C is 100, L is 50, X is 10, V is 5, and I is 1.

How to tell if a battery is still good

To tell if your battery is still in good condition, lift it a few centimeters above a table and let it drop. If it bounces and falls, it is empty.

We would touch our left ring finger (for 7) to the middle finger of the right hand (for 8).

Now, count the touching fingers and all the fingers beneath them. In this case, we have 5 (the touching middle and ring finger, the ring finger from the right hand, and the two pinkies). These bottom numbers represent 10s, so 5 x 10 is 50.

Now, all the fingers on top of the touching fingers represent 1s, and they need to be multiplied together. In this case, we have 3 top fingers on the left hand (the middle, index, and thumb) and 2 fingers on the right hand (index and thumb). If we multiply them, 3 x 2 is 6.

Add the product from the top fingers to the product from the bottom fingers (50+6), and you get the answer, 56.

How to multiply the number 9 using your fingers

If you need to multiply a small number by 9, then the method is even easier.

Put both your hands up, with your fingers outstretched. The first finger (the left pinky) represents the number 1, the left ring finger represents the number 2, the left middle finger the number 3, and so on, and so on, all the way to 10. Now, let’s say you want to multiply 9 by 3. First, you would bend the third finger downwards (the left middle finger).

Now, count the fingers to the left and right of the bent finger. In this case, we have 2 on the left and 7 on the right. Put them together, and the answer is 27.

How to quickly measure the degrees of an angle

You can easily calculate the degrees of an angle by using one hand. First, spread your fingers as much as possible. Next, put your palm down onto the angle you want to measure, with the pinky finger touching the bottom side. This pinky represents o°. Now, just see which finger the angle comes closest to: the angle between the thumb and pinky finger is 90°, between pinky and index is 60°, between pinky and middle is 45°, and between pinky and ring is 30°.